Hello,
Is there any way to use iframe with Forge Custom UI App on issue page and can we call api in custom ui with using iframe? We have difficulties in authorization. I mean, whenever we use iframe in html file of the custom ui app, there is an error appear in the iframe.

And it says "the site is blocked."
I know there is a limitation for security issues but could not run the iframe on any site. At least, if you guys tell me which sites can be used on iframe, I will be appreciate.